Sökning: "predator-prey relationships"

Hittade 5 avhandlingar innehållade orden predator-prey relationships.

  1. 1. Temporal relationships between fish-eating birds and their prey in a north Swedish river

    Författare :Kjell Sjöberg; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Seasonal and diel activity; food consumption; predator-prey relationships; fish-eating birds; anadromous fish; Mergus merganser; M. serrator; Sterna spp.; Larus spp.; Lampetra fluviatilis; Gasterosteus aculeatus;

    Sammanfattning : The seasonal and diel feeding habits of the goosander, Mergus merganser, the red-breasted merganser, M. serrator, gulls (Larus canus, L. argentatus and L. fuscusj and terns, Sterna hirundo/paradisaea were studied at 64V05'N. LÄS MER

  2. 2. Population-level consequences of spatial interactions

    Författare :Henrik Sjödin; Göran Englund; Åke Brännström; Per Lundberg; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : How is the nature of populations governed by the movement decisions made by their members? This is the core question in this thesis. To answer this question, I first assume that s movement decisions are based on conditions in their local environment. LÄS MER

  3. 3. Functionality of wet grasslands as green infrastructure : waders, avian predators and land covers in Northern Europe

    Författare :Michael Manton; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Habitat loss is a global issue that affects land cover patterns, ecological processes and the distribution and abundance of species. As a result, many conservation approaches have appeared, such as the European Union’s green infrastructure (GI) policy and UNESCO’s Biosphere Reserve (BR) concept. LÄS MER

  4. 4. Long Term Studies of Insect Abundances in Temporary Wetlands in Relation to Hydrology, Predation and Bti

    Författare :Thomas Persson Vinnersten; Jan O Lundström; Örjan Östman; William Walton; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; floodwater mosquitoes; mosquito control; predation; aquatic insects;

    Sammanfattning : Long-term insect abundances have been studied to investigate factors structuring the insect communities of the temporary wetlands around the River Dalälven floodplain. In the wet meadows and swamps in the River Dalälven floodplains recurrent floods are the ultimate prerequisite for high production of floodwater mosquitoes. LÄS MER

  5. 5. Quantifying Risk in Epidemiological and Ecological Contexts

    Författare :Stefan Sellman; Uno Wennergren; Bo Ebenman; Meggan Craft; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : The rates of globalization and growth of the human population puts ever increasing pressure on the agricultural sector to intensify and grow more complex, and with this intensification comes an increased risk of outbreaks of infectious livestock diseases. At the same time, and for the same reasons, the detrimental effect that humans have on other species with which we share the environment has never been more apparent, as the current rates of species loss from ecological communities rival those of ancient mass extinction events. LÄS MER